Water color pigment solutions for use with reflectance-based diagnostic analyzers

ABSTRACT

Provided herein are color charts and water color pigment solutions useful, for example, in the calibration of reflectance-based diagnostic analyzers.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/276,559, filed Jan. 8, 2016, the disclosure of which is herebyincorporated by reference in its entirety.

TECHNICAL FIELD

Provided herein are color charts and water color pigment solutionsuseful, for example, in the calibration of a reflectance-baseddiagnostic analyzer.

BACKGROUND

The diagnostic evaluation of sample liquids (such as, but not limitedto, whole blood, urine, saliva, and plasma) often involves dispensing aportion of the sample liquid onto a reagent pad and then observing thechanges to the reagent pad (changes in color, for example). Diagnosticanalyzers, such as the CLINITEK Novus® urine analyzer, can be used toinspect reagent pads for color changes via reflectance-basedmeasurement(s) (as opposed to an absorbance based measurement). TheCLINITEK Novus® urine analyzer reports values for the following results:yellow, dark yellow, orange, red, green, and other.

Urine can have a variety of colors as a result of a patient's clinicalstate or the elimination of drugs from the body. Use of a diagnosticanalyzer to determine these colors on a reagent pad can have asignificant impact on the patient's diagnosis. It is therefore importantto evaluate the color output of these instruments for accuracy.

SUMMARY

Provided herein are color charts comprising a surface material havingone or more color swatches, wherein the color swatches comprise one ormore layers of a dried water color pigment solution, wherein the watercolor pigment solution contains color pigment molecules. Kits comprisingthe color charts are also provided.

Also disclosed are water color pigment solutions comprising a suspensionof one or more water color pigments and urine or a solution that mimicsurine. Kits comprising the water color pigment solutions are alsoprovided.

Methods of calibrating a reflectance-based diagnostic analyzer are alsoprovided, wherein the methods comprise: inserting any of the hereindisclosed color charts or water color pigment solutions into thereflectance-based diagnostic analyzer, wherein the color chart or thewater color pigment solutions have a known color; obtaining reflectancevalues for the color chart or the water color pigment solutions; and ifthe obtained reflectance values do not correspond to the known color ofthe color chart or the water color pigment solutions, calibrating theanalyzer such that the reflectance values correspond to the known colorof the color chart or the water color pigment solutions.

BRIEF DESCRIPTION OF THE DRAWINGS

The summary, as well as the following detailed description, is furtherunderstood when read in conjunction with the appended drawings. For thepurpose of illustrating the disclosed color charts, water color pigmentsolutions, methods, and kits there are shown in the drawings exemplaryembodiments of the color charts, water color pigment solutions, methods,and kits; however, the color charts, water color pigment solutions,methods, and kits is not limited to the specific embodiments disclosed.In the drawings:

FIG. 1 illustrates an exemplary color chart.

FIG. 2 illustrates the distribution of various CLINITEK Novus® Watercolor pigment solutions across the CLINITEK Novus® hue range. A total of26 (6 Base Solutions and 20 novel solutions) were analyzed on a singleCLINITEK Novus® to determine the hue values.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The disclosed color charts, water color pigment solutions, methods, andkits may be understood more readily by reference to the followingdetailed description taken in connection with the accompanying figures,which form a part of this disclosure. It is to be understood that thedisclosed color charts, water color pigment solutions, methods, and kitsare not limited to the specific color charts, water color pigmentsolutions, methods, and kits described and/or shown herein, and that theterminology used herein is for the purpose of describing particularembodiments by way of example only and is not intended to be limiting ofthe claimed color charts, water color pigment solutions, methods, andkits.

Unless specifically stated otherwise, any description as to a possiblemechanism or mode of action or reason for improvement is meant to beillustrative only, and the disclosed color charts, water color pigmentsolutions, methods, and kits are not to be constrained by thecorrectness or incorrectness of any such suggested mechanism or mode ofaction or reason for improvement.

Where a range of numerical values is recited or established herein, therange includes the endpoints thereof and all the individual integers andfractions within the range, and also includes each of the narrowerranges therein formed by all the various possible combinations of thoseendpoints and internal integers and fractions to form subgroups of thelarger group of values within the stated range to the same extent as ifeach of those narrower ranges was explicitly recited. Where a range ofnumerical values is stated herein as being greater than a stated value,the range is nevertheless finite and is bounded on its upper end by avalue that is operable within the context of the present disclosure.Where a range of numerical values is stated herein as being less than astated value, the range is nevertheless bounded on its lower end by anon-zero value. It is not intended that the scope of the invention belimited to the specific values recited when defining a range. All rangesare inclusive and combinable.

When values are expressed as approximations, by use of the antecedent“about,” it will be understood that the particular value forms anotherembodiment. Reference to a particular numerical value includes at leastthat particular value, unless the context clearly dictates otherwise.

It is to be appreciated that certain features of the disclosed colorcharts, water color pigment solutions, methods, and kits which are, forclarity, described herein in the context of separate embodiments, mayalso be provided in combination in a single embodiment. Conversely,various features of the disclosed color charts, water color pigmentsolutions, methods, and kits that are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany subcombination.

Any reference to “one embodiment” or “an embodiment” means that aparticular element, feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodiment.The appearances of the phrase “in one embodiment” in various places inthe specification are not necessarily all referring to the sameembodiment.

As used herein, the singular forms “a,” “an,” and “the” include theplural.

Various terms relating to aspects of the description are used throughoutthe specification and claims. Such terms are to be given their ordinarymeaning in the art unless otherwise indicated. Other specificallydefined terms are to be construed in a manner consistent with thedefinitions provided herein.

The term “about” is used to encompass variations of ±10% or less,variations of ±5% or less, variations of ±1% or less, variations of±0.5% or less, or variations of ±0.1% or less from the specified value.

The term “comprising” is intended to include examples encompassed by theterms “consisting essentially of” and “consisting of”; similarly, theterm “consisting essentially of” is intended to include examplesencompassed by the term “consisting of”.

Unless expressly stated to the contrary, “or” refers to an inclusive“or” and not to an exclusive “or.” For example, a condition A or B issatisfied by anyone of the following: A is true (or present) and B isfalse (or not present); A is false (or not present) and B is true (orpresent); and both A and B are true (or present). An inclusive “or” maybe understood as being the equivalent to at least one of condition A orB.

The following abbreviations are used herein: Dark Yellow (D. Yellow);Middlebury Street Plant General Method (MSPGM); Online DocumentLibrary-Middlebury Street (ODL); National Institute of Standards andTechnology (NIST).

Color Charts and Water Color Pigment Solutions

It is important to evaluate the color output of diagnostic instrumentsto ensure accuracy. This evaluation can be done with the use of colorsolutions which are typically made from color dyes. For consistentresults, this color solution should be compared to National Institute ofStandards and Technology (“NIST”) traceable standards yielding colorvalues. Because color dye solutions cannot be accurately measured usingreflectance-based systems, NIST traceable instruments that giveabsorbance values are used. Making an accurate, direct comparisonbetween the absorbance values of the color dye to an NIST standard,however, is extremely difficult. Color output can be measured usingabsorbance-based methods, but the resulting absorbance values do notcorrectly correlate to reflectance readings (obtained by, for example, adiagnostic analyzer). Accordingly, color dyes are inadequate forevaluating the color output values from reflectance instruments.

Color reference charts, another reference tool, can be created byprinting ink. For example, various colors can be printed on a papersubstrate which can then be evaluated by the reflectance-baseddiagnostic analyzer. Getting accurate colors using ink, however, isdifficult. The intensity of color ink is determined by mixing primarycolors and white prior to applying the ink to a substrate, which makesit extremely difficult to precisely control the intensity (or hue) ofthe ink once it is on the substrate and dry. Moreover, ink sits on topof the substrate to which it is applied rather than being absorbed intothe substrate.

The disclosed color charts and water color pigment solutions offeradvantages over prior reference charts and color solutions. For example,water color pigments are employed in the disclosed color charts andwater color pigment solutions to make a standardized colorchart/solution that can be analyzed with an independent NIST traceablereflective color instrument.

Disclosed herein are color charts comprising a surface material havingone or more color swatches, wherein the color swatches comprise one ormore layers of a dried water color pigment solution, wherein the watercolor pigment solution contains color pigment molecules.

The hue of each color swatch in the color chart is related to the numberof layers of the dried water color pigment solution present on theswatch. A color swatch having multiple layers of a dried water colorpigment solution can have a darker hue compared to a color swatch havingfewer layers of the dried water color pigment solution. For example, acolor swatch having 5 layers of dried water color pigment solution willbe darker than a color swatch having 1 layer of the same dried watercolor pigment solution.

The disclosed color charts can comprise one or more color sections,wherein the one or more color swatches are arranged in the one or morecolor sections. In some embodiments, for example, the one or more colorsections can comprise a red color section, an orange color section, ayellow color section, a green color section, or any combination thereof.Each of these color sections can be further subdivided based upon theintensity of the color. For example, in some embodiments, the yellowcolor section can comprise a dark yellow color section, a light yellowcolor section, or both a dark yellow color section and a light yellowcolor section.

The color sections can comprise the following hues:

-   -   a. the red color section can comprise a hue from about 347.1 to        about 360.0 or from about 0.0 to about 20.0;    -   b. the orange color section can comprise a hue from about 24.1        to about 36.7;    -   c. the yellow color section can comprise a hue from about 38.4        to about 57.0;    -   d. the green color section can comprise a hue from about 74.5 to        about 120.0; or    -   e. any combination of a-d.

The color of the one or more color swatches can correlate with a colorof one or more water color pigment solutions. Exemplary water colorpigment solutions are provided herein.

The color swatches comprise a dried water color pigment solution, which,prior to being dried, can comprise a suspension of one or more watercolor pigments. Thus, the color swatches comprise color pigmentmolecules.

Exemplary water color pigments include orange water color pigments,brilliant red water color pigments, medium yellow water color pigments,cobalt blue water color pigments, raw umber water color pigments, sapgreen water color pigments, or any combination thereof. In someembodiments, the one or more water color pigments can comprise orange,brilliant red, medium yellow, cobalt blue, raw umber, sap green, or anycombination thereof.

The color swatches can be created from water color pigments of the samecolor or from a mixture of water color pigments of different colors. Insome embodiments, the one or more water color pigments comprises acombination of:

-   -   a) brilliant red and cobalt blue;    -   b) brilliant red and orange;    -   c) orange and medium yellow;    -   d) medium yellow and sap green; or    -   e) sap green and cobalt blue.

The color swatches can be prepared from any of the water color pigmentsolutions disclosed herein, which can be applied to a reagent-less pador a sheet of paper (such as water color paper) and allowed to dry. Asopposed to applying a dye, or printing colored ink, onto a surfacematerial, application of the disclosed water color pigment solutionsonto the surface material will result in a layer of color pigmentmolecules on the surface material. Application of additional layers ofthe water color pigment solution will, upon drying, result in a darkerhue. These color intensities can be used to mimic urine concentrations.Use of water color pigment solutions results in a more accurate colorintensity, or hue, that can be traced to an NIST standard and evaluatedby the reflectance-based diagnostic analyzer.

An exemplary color chart is shown in FIG. 1. As shown in the figure, thecolor chart can comprise a Red, Orange, Dark Yellow (D. Yellow), Yellow,and Green color section, each color section having one or more colorswatches. The individual color swatches are labeled using the followingformat: color—red (R), orange (O), d. yellow (D), yellow (Y), and green(G); column within each color section (1, 2, 3, etc.); and row withineach color section (a, b, c, d, etc.). The intensity of the color swatchcan be related to the number of layers of the dried water color pigmentsolution present on the swatch. For example, for each column of colorswatches (R1 a, R2 a, R3 a, for example) the swatches in row “a” havemore layers of the dried water color pigment solution compared to theswatches in rows “b,” “c,” and “d.” Thus, the hue of the “a” swatches isdarker than that of the other rows. The color sections can also comprisecolor swatches made from dried water color pigment solutions ofdifferent hues. In the figure, for example, the color swatches in thecolumn labeled “1,” are made from a water color pigment solution havinga different hue than the color swatches in the column labeled “2.”

Also provided are water color pigment solutions comprising a suspensionof one or more water color pigments. The one or more water color pigmentsolutions can be suspended in water, urine, or a solution that mimicsurine, such as water comprising an appropriate amount of salt to mimicthe isotonic strength of urine.

The water color pigment solutions can be prepared by weighing theappropriate amount of water color pigment and combining the water colorpigment with the appropriate solution. For example, water color pigmentscan be measured at a predetermined weight on an analytical balance,transferred to a beaker, and diluted with a specific volume of urine orpurified water. In embodiments wherein the water color pigments arediluted in purified water, salt (such as NaCl) can be added to mimic theisotonic strength of normal urine. Many water color pigment solutionscan be developed due to the variety of available color pigments. Thepigments can be combined and the concentration altered to achieve aneven greater array of colors as exemplified in the Examples herein.

The one or more water color pigments can comprise orange, brilliant red,medium yellow, cobalt blue, raw umber, sap green, or any combinationthereof. The water color pigment solutions can be created from watercolor pigments of the same color. In some embodiments, the water colorpigments can comprise:

-   -   a) Orange at a concentration of about 4 mg/ml to about 5 mg/ml;    -   b) Brilliant red at a concentration of about 4 mg/ml to about 5        mg/ml;    -   c) Medium yellow at a concentration of about 7 mg/ml to about 8        mg/ml;    -   d) Cobalt blue at a concentration of about 8 mg/ml to about 9        mg/ml;    -   e) Raw umber at a concentration of about 6 mg/ml to about 7        mg/ml; or    -   f) Sap green at a concentration of about 17 mg/ml to about 18        mg/ml.

The water color pigment solutions can be created from a mixture of watercolor pigments of different colors. In some embodiments, the one or morewater color pigments can comprise a combination of:

-   -   a) brilliant red and cobalt blue;    -   b) brilliant red and orange;    -   c) orange and medium yellow;    -   d) medium yellow and sap green; or    -   e) sap green and cobalt blue.

Exemplary mixtures of water color pigments comprise:

-   -   a) about 6.5 parts brilliant red to about 1 part cobalt blue;    -   b) about 1 part brilliant red to about 2 parts orange;    -   c) about 2 parts orange to about 1 part medium yellow;    -   d) about 14 parts medium yellow to about 1 part orange;    -   e) about 4 parts medium yellow to about 1 part sap green;    -   f) about 1 part medium yellow to about 2 parts sap green;    -   g) about 6.5 parts sap green to about 1 part cobalt blue; or    -   h) about 2 parts sap green to about 1 part cobalt blue.

The mixtures of water color pigments in a)-h) above can be furtherdiluted. In some embodiments, the mixtures can be further diluted withurine. In some embodiments, the mixtures can be further diluted withwater. In some embodiments, the mixtures can be further diluted with asolution configured to mimic urine, such as water comprising anappropriate amount of salt to mimic the isotonic strength of urine.Exemplary dilutions, which can be made with urine, water, or the urinemimic include:

-   -   the water color pigment of a) further diluted 1:4;    -   the water color pigment of b) further diluted 1:30;    -   the water color pigment of c) further diluted 1:4 or 1:10;    -   the water color pigment of d) further diluted 1:4 or 1:15;    -   the water color pigment of e) further diluted 1:4 or 1:13;    -   the water color pigment of g) further diluted 1:10; or    -   the water color pigment of h) further diluted 1:9.

The water color pigment solutions can further comprising a preservative.Suitable preservatives comprise, for example, sodium azide.

Any of the above disclosed water color pigment solutions can be used tocreate the herein disclosed color charts. For example, the color pigmentsolutions can be layered onto a water color paper or reagent-less pad.By increasing the number of layers of water color pigment solutions, thecolor intensities can be precisely controlled.

The disclosed water color pigment solutions can be used byreflectance-based instruments to calibrate the sensors and correct theircolor value readings.

Methods of Calibrating a Reflectance-Based Diagnostic Analyzer

Provided herein are methods of calibrating a reflectance-baseddiagnostic analyzer comprising:

-   -   inserting any of the disclosed color charts or any of the        disclosed water color pigment solutions into the        reflectance-based diagnostic analyzer, wherein the color chart        or the water color pigment solutions have a known color;    -   obtaining reflectance values for the color chart or the water        color pigment solutions; and    -   if the obtained reflectance values do not correspond to the        known color of the color chart or the water color pigment        solutions, calibrating the analyzer such that the reflectance        values correspond to the known color of the color chart or the        water color pigment solutions.

In some embodiments, the reflectance-based diagnostic analyzer can be aCLINITEK Novus® instrument. In some embodiments, the reflectance-baseddiagnostic analyzer can comprise a portable diagnostic analyzer. Oneexample of a portable diagnostic analyzer is a digital camera coupled toa processor—such as those found in a smart phone, tablet, or other handheld diagnostic analyzer (collectively “portable diagnostic analyzers”).An illustrative inventive method of using a portable diagnostic analyzerincludes the use of the color charts herein as a reference to improveaccuracy/calibration of near patient or at home testing. Another methodincludes teaching a patient to use a portable diagnostic analyzer andany of the disclosed color charts as a reference to improveaccuracy/calibration of near patient or at home testing.

Kits

Further provided are kits comprising any of the herein disclosed colorcharts or any of the herein disclosed water color pigment solutions andinstructions for using the color charts or water color pigmentsolutions. In some embodiments, the kits comprise any of the hereindisclosed color charts and instructions for using the color charts. Insome embodiments, the kits comprise any of the herein disclosed watercolor pigment solutions and instructions for using the water colorpigment solutions.

In some embodiments, the instructions explain to a user of the kit howto calibrate a reflectance-based diagnostic analyzer.

EXAMPLES

The following examples are provided to further describe some of theembodiments disclosed herein. The examples are intended to illustrate,not to limit, the disclosed embodiments.

Experimental Design:

Twenty-one (21) contrived urine color solutions were developed usingwater color pigments. These solutions correlate to a CieLab DEinstrument which was calibrated to the International Committee forIllumination (CIE) publication No. 15.2. A color chart for matching toNovus color blocks was also developed from contrived color solutions.

The contrived urine color solutions were evaluated with one (1)replicate on each of three (3) CLINITEK Novus® instruments (S/N P100046,S001165, and S001109) using a single lot of CLINITEK Novus® 10-Wayreagents (lot K117123). Five (5) visual readers evaluated each samplecomparing the color of the sample to a color chart.

Development of Color Solutions:

Prior art color solutions do not have the variation needed to evaluatethe range of the CLINITEK Novus® color blocks. Thus, new color solutionswere developed using water color pigments, of which seventeen (17)individual pigments were selected for processing. During initialdevelopment, quantities of each pigment paste were diluted with polishedwater, and each solution was evaluated with the CLINITEK Novus® todetermine the hue value (data not shown). The pigments in Table 1 andBase Solutions generated from the pigments (Table 2) were selected forfurther evaluation based on the CLINITEK Novus® hue value and colorblock ranges.

TABLE 1 Water Color Pigments Materials Color Source Part No. Used inSolution No. Orange Reeves 8404150 5-Orange Brilliant Red Reeves 84042306-RedBril Medium Yellow Reeves 8404120 8-YelMed Cobalt Blue Grumbacher1417335065 13-BluCob Raw Umber Grumbacher 1417335093 15-Umber Sap GreenReeves 8404428 16-GreSap

The six (6) selected pigments were used to generate the Base Solutions,as shown in Table 2. Due to the small tubes in which the pigments come,a small spatula was needed to transfer the pigment from the tube to thediluting container. The amount of pigment for each color was determinedby pre-weighing the spatula on an analytical balance and then weighingthe spatula with the pigment. To generate the Base Solutions, theappropriate amount of pigment was combined with a solution containingurine having normal analyte levels (as measured on a Multistix 10SGurine strip) and sodium azide. A total of 940 mL was needed to make thefinal solutions; 628 mL for base solutions and 312 for dilutions.Accordingly, 1500 mL of negative urine was collected, and to this 300 mgof sodium azide was added as a preservative. The “Volume Needed” wasbased on what was required to make the Base Solutions, Target Solutions,and the Target Solution dilutions using a 40 mL, final volume. Anadditional 10 mL were added to allow for solution preparation. The mg/mLwas based on the initial development of the color solutions.

TABLE 2 Base Solution Preparation Amounts Volume Volume + 10 mL PigmentBase Color Needed (ml) (mL) mg/mL (mg) 5-Orange 70 80 4.59 365.36-RedBril 106 116 4.66 541.8 8-YelMed 202 212 7.07 1496.5 13-BluCob 2838 8.73 330.7 15-Umber 55 65 6.50 422.5 16-GreSap 108 118 17.02 2005.0

Twenty (20) Test Solutions were prepared using various combinations ofthe Base Solutions (data not shown). The Test Solutions used the BaseSolutions in different ratios to obtain a variety of colors across theCLINITEK Novus® hue range. The twenty (20) additional solutions, alongwith six (6) of the Base Solutions, were analyzed on a single CLINITEKNovus® to determine the hue values. This data was sorted and placed intothe graph in FIG. 2, which shows the distribution across the CLINITEKNovus® hue range. Solution 13 Cobalt Blue was not tested and only usedfor mixing purposes.

Based on the above analysis, 11 combinations were selected as TargetSolutions. Three (3) solutions were designated for each of the followingCLINITEK Novus® color blocks: Red, Yellow, and Green, along with two forthe Orange color block (Table 3). The Target Solutions were preparedaccording to Table 3, which lists the Base Solutions used for eachtarget along with the percent volume for that solution. An additional10% of volume was added to allow for processing.

TABLE 3 Target Solution Preparation Volumes Target Base Percent TotalTotal + 10% Solution Solution Volume (mL) (ml) Color Block 34-Red4 686.67 43.33 47.67 Red 13 13.33 6.67 7.33 6-RedBril 6 100.00 40.00 44.0033-Red3 6 33.33 13.33 14.67 5 66.67 26.67 29.33 25-Orng4 5 66.67 33.3336.67 Orange 8 33.33 16.67 18.33 15-Umber 15 100.00 50.00 55.00 36-Yel38 93.33 46.67 51.33 Dark 5 6.67 3.33 3.67 Yellow 8-YelMed 8 100.00 66.6773.33 30-YelGrn1 8 80.00 40.00 44.00 16 20.00 10.00 11.00 38-Grn5 833.33 13.33 14.67 Green 16 66.67 26.67 29.33 20-Grn3 16 86.67 34.6738.13 13 13.33 5.33 5.87 22-GrnBlu1 16 66.67 26.67 29.33 13 33.33 13.3314.67

The 11 Target Solutions were diluted in varying amounts depending on thesolution and its concentration (a total of 15 dilutions ranging from ¾to 1/80 were used; however, not all Target Solutions were diluted in thesame ratios). 65 diluted solutions were generated from the 11 TargetSolutions. The dilutions were analyzed on a CLINITEK Novus® to determinethe hue value (data not shown). Using both the compiled CLINITEK Novus®data and visual analysis, 21 Final Color Solutions (Table 4) wereselected.

The Final Color Solutions were designated in terms of dilutions. Thecolumn headings list the dilution number along with the ratio of targetsolution to urine. Dilution 1 was the undiluted target solution. Afterthe diluting process was complete, solutions 36-Yel3 Dil. 10, 8-YelMedDil. 8 & Dil. 10 and 30-YelGrn1 Dil. 9 from Table 4 were further diluted1:3 with water to obtain the final solutions for the Yellow color block(water was used for this dilution because the negative urine color addedto the solution intensity). The Final Color Solutions were refrigeratedin capped containers.

TABLE 4 Final Color Solutions Target Dil. 1 Dil. 3 Dil. 6 Dil. 8 Dil. 9Dil. 10 Dil. 12 Dil. 13 Soln Soln 1:1 2:3 1:4 1:10 1:13 1:15 1:9 1:3034-Red4 Target 40.0 — 10.0 — — — — — Urine  0.0 — 30.0 — — — — — 6-Target 40.0 — — — —  2.667 — — RedBril Urine  0.0 — — — — 37.333 — —33-Red3 Target — — — — — — —  1.333 Urine — — — — — — — 38.667 25-Target — — 10.0  4.0 — — — — Orng4 Urine — — 30.0 36.0 — — — — 15-Target — — 10.0 — — — — — Umber Urine — — 30.0 — — — — — 36-Yel3 Target40.0 — 10.0 — —  2.667 — — Urine  0.0 — 30.0 — — 37.333 — — 8- Target40.0 26.667 —  4.0 —  2.667 — — YelMed Urine  0.0 13.333 — 36.0 — 37.333— — 30- Target — — 10.0 —  3.077 — — — YelGrn1 Urine — — 30.0 — 36.923 —— — 38-Grn5 Target 40.0 — — — — — — — Urine  0.0 — — — — — — — 20-Grn3Target 40.0 — —  4.0 — — — — Urine  0.0 — — 36.0 — — — — 22- Target — —— — — —  4.444 — GrnBlu1 Urine — — — — — — 35.556 —

Color Chart Development:

There are no hard color standards (i.e. paper-based or non-liquid)available for CLINITEK Novus® color solutions. Therefore, a color chartwas developed using the same material that the Final Color Solutionswere made from. To create the color chart, a series of one (1) inchsquares were penciled onto cold press artist paper in a 6×10 pattern.Using a ½ inch width paint brush, some of the Target Solutions weresystematically applied to the squares in a series of increasing coatingapplications, the greater the number of coatings the more intense thecolor. There were 4 squares for the Red, Orange, and Green targetcolors. 5 squares were used for the yellow target color. The extrasquare was used to help differentiate between Dark Yellow and Yellow.Table 5 lists the number of coatings needed to obtain the desired colorintensities.

TABLE 5 Color Chart Swatch Coatings Target Solution Square 1 Square 2Square 3 Square 4 Square 5 34-Red4 1 5 9 16 — 6-RedBril 1 5 9 16 —33-Red3 1 5 9 16 — 25-Orng4 1 5 9 16 — 15-Umber 1 5 9 16 — 28-Orng7 1 59 16 — 36-Yel3 2 4 9 15 16 8-YelMed 2 4 9 15 16 30-YelGrn1 2 4 9 15 1638-Grn5 2 5 9 16 — 20-Grn3 2 5 9 16 — 22-GrnBlu1 2 5 9 16 —

The coated squares were cut into individual swatches, aligned, andattached to a cardboard backing. The cold press paper was pre-laminatedwith double sided adhesive before coating began so that the swatchescould easily be attached to the chart. All swatches were used except forsquare 3 from the yellow Target Solutions (#36-Ye13, 8-YelMed &30-YelGrn1). This enabled Yellow and Dark Yellow to be distinguished.Labels were made and attached to the chart. An exemplary color chart isshown in FIG. 1.

The chart was divided into 5 color sections and each section contained 3columns of color swatches. The columns were further divided into rows ofdecreasing swatch color intensity.

The Mercury DataColor instrument (Serial Number 1007) was used to obtainCieLab data readings from each of the 48 swatches on the color chart(Tables 6 to 11). The CieLab readings were converted to HSV values. TheCieLab data readings and HSV values are color space systems used todefine colors and hues in numerical terms. The CLINITEK Novus® uses theHSV system. To compare the Novus to the color swatches, the MercuryDataColor was employed, which used the CieLab color space system. Thisdata was converted to HSV values. For each of Tables 6 to 11 thefollowing applies: L, a, b, c, h and H, S, V represented 2 types ofcolor space indicators. “L” indicates lightness; “a” indicates thered/green component; “b” indicates the yellow/blue component; “c” and“h” indicate the other parts of the system; “H” indicates Hue; “S”indicates the saturation component; and “V” indicates the value oflightness.

TABLE 6 Color Chart DataColor Instrument Readings: Red Color Block BlockRed Column 1 (“R1”) Red Column 2 (“R2”) Row a b c d a b c d DataColor L64.33 75.80 83.30 89.15 70.34 77.99 83.13 90.88 a 28.58 20.13 12.59 5.7837.65 25.85 17.60 4.58 b 3.11 3.28 3.91 4.61 12.54 8.32 6.53 5.63 c28.75 20.39 13.19 7.39 39.68 27.16 18.77 7.26 h 6.20 9.26 17.25 38.5518.42 17.84 20.34 50.88 Converted H 347.1 350.8 358.3 12.5 355.7 356.60.0 17.5 S 0.337 0.230 0.150 0.099 0.404 0.284 0.202 0.100 V 0.809 0.8840.919 0.938 0.950 0.959 0.959 0.951

TABLE 7 Color Chart DataColor Instrument Readings: Red and Orange ColorBlocks Block Red Column 3 (“R3”) Orange Column 1 (“O1”) Row a b c d a bc d DataColour L 70.32 78.12 83.83 90.96 75.04 80.81 84.76 90.88 a 39.5626.55 18.83 4.30 33.84 22.72 15.17 4.36 b 40.26 28.71 22.34 6.81 50.0136.60 27.06 12.51 c 56.45 39.10 29.22 10.71 60.38 43.08 31.02 13.24 h45.50 47.24 49.88 66.33 55.91 58.16 60.72 70.77 Converted H 15.6 16.818.6 20.0 24.1 24.6 24.9 28.6 S 0.604 0.445 0.341 0.110 0.635 0.4770.367 0.170 V 0.999 1.000 1.000 0.962 1.000 1.000 1.000 0.969

TABLE 8 Color Chart DataColor Instrument Readings: Orange Color BlockBlock Orange Column 2 (“O2”) Orange Column 3 (“O3”) Row a b c d a b c dDataColor L 56.40 70.43 78.90 89.23 79.82 84.94 87.73 92.04 a 14.7811.04 7.26 1.92 20.95 11.27 6.05 1.11 b 33.62 31.63 26.11 14.25 53.4637.80 27.65 12.39 c 36.72 33.50 27.10 14.38 57.42 39.45 28.30 12.44 h66.27 70.76 74.45 82.31 68.61 73.39 77.65 84.89 Converted H 28.5 30.332.3 35.7 31.9 32.1 36.4 36.7 S 0.563 0.451 0.348 0.175 0.618 0.4460.418 0.146 V 0.691 0.824 0.886 0.938 1.000 1.000 1.000 0.958

TABLE 9 Color Chart DataColor Instrument Readings: Yellow Color BlockBlock D. Yellow Yellow D. Yellow Yellow Column 1 Column 1 Column 2Column 2 (“D1”) (“Y1”) (“D2”) (“Y2”) Row a b c d a b c d DataColor L84.37 84.90 90.38 91.80 88.53 88.79 91.51 92.11 a 9.84 9.08 0.75 0.02−1.76 −1.87 −2.14 −1.66 b 54.81 52.59 24.71 17.35 57.67 56.50 24.9218.35 c 55.69 53.36 24.72 17.35 57.70 56.53 25.01 18.42 h 79.83 80.2188.26 89.94 91.75 91.90 94.90 95.17 Converted H 38.4 38.3 40.3 40.9 46.646.7 45.7 44.3 S 0.587 0.563 0.267 0.191 0.567 0.555 0.254 0.188 V 1.0001.000 0.970 0.961 0.990 0.991 0.961 0.966

TABLE 10 Color Chart DataColor Instrument Readings: Yellow and GreenColor Blocks Block D. Yellow Yellow Column 3 Column 3 (“D3”) (“Y3”)Green Column 1 (“G1”) Row a b c d a b c d DataColour L 83.21 84.66 90.7791.88 76.70 84.50 88.10 91.06 a −12.43 −11.04 −4.12 −2.53 −23.13 −13.86−8.70 −4.44 b 56.59 52.71 23.90 16.40 46.53 33.38 23.97 15.29 c 57.9453.85 24.25 16.59 51.96 36.14 25.50 15.92 h 102.39 101.83 99.77 98.78116.43 112.54 109.94 106.18 Converted H 57.0 55.3 50.4 48.2 74.5 67.062.4 56.3 S 0.557 0.512 0.234 0.165 0.498 0.321 0.220 0.141 V 0.8540.875 0.936 0.940 0.781 0.850 0.880 0.914

TABLE 11 Color Chart DataColor Instrument Readings: Green Color BlockBlock Green Column 2 (“G2”) Green Column 3 (“G3”) Row a b c d a b c dDataColor L 69.37 80.54 85.21 90.36 66.38 78.94 85.04 89.91 a −23.77−15.93 −11.19 −4.66 −21.38 −14.17 −9.30 −4.67 b 29.38 22.81 18.05 11.0716.12 13.06 10.61 8.53 c 37.79 27.83 21.24 12.01 26.77 19.27 14.23 9.72h 128.97 124.93 121.79 112.82 142.98 137.33 131.22 118.68 Converted H92.7 84.7 79.5 65.2 120.0 106.9 96.0 75.8 S 0.362 0.244 0.182 0.1010.232 0.156 0.115 0.081 V 0.706 0.813 0.855 0.899 0.672 0.794 0.8510.895

Final Solution Testing:

The Final Color Solutions were randomized and renumbered so that similarcolors were not next to each other. Solutions were transferred toCLINITEK Novus® tubes and placed in racks for easier handling.

The Final Color Solution testing was performed by comparing the resultsfrom visual readings and Novus analysis. As stated above, all FinalColor Solutions were tested on each of three (3) Novus instruments andthe data was collected with the ASTM data collection software. Visualtesting was completed by five (5) individuals who read the solutionsindependently. Each individual was given both the Final Color Solutionsand the color chart. The layout of the color chart was explained(divided into the 5 CLINITEK Novus® color Blocks (Red, Orange, DarkYellow, Yellow and Green)), and each individual was instructed to matchthe Final Color Solutions to a swatch on the color chart. Eachindividual read one Final Color Solution at a time in the order that thesolutions were presented. As the result of each Final Color Solution wasdetermined, an independent recorder tallied the results on the recordform. The recorder also confirmed results with the reader to ensure thedata was correct.

Data Analysis:

The CLINITEK Novus® data files were processed through the UDAT dataanalysis program and the means and standard deviations (SD) data werecalculated with a Microsoft Excel spreadsheet. The visual results werealso transferred to a spreadsheet. A frequency table was generated tocompare visual results to CLINITEK Novus®.

The goal of this testing was to define the degree of correlation betweenthe CLINITEK Novus® and visual reads for the Final Color Solutions;therefore, there were no pass/fail criteria.

All three (3) CLINITEK Novus® instruments read the 20 Final ColorSolutions the same. However, there were some variation between theindividuals that performed the visual analysis. The comparison of theresults from the CLINITEK Novus® instruments vs. the visual analysis isshown in Table 12. In this table, the color detected by the instrumentsis provided in the first column (labeled CLINITEK Novus® Results) andthe results of the visual analysis is provided under the column labeledwith the color (Red, Orange, Dark Yellow, Yellow, Green). As shown inthe Table, the Final Color Solutions Red, Dark Yellow, and Green weredetected 100% by both the instruments and individual readers. For theOrange samples, 3 of the 20 were labeled as Red with the visualanalysis. For the Yellow samples, 1 was labeled as green by one visualreader.

TABLE 12 Frequency Table: CLINITEK Novus ® vs Visual Visual ResultsCLINITEK Color Novus ® Dark Grand Results Red Orange Yellow Yellow GreenTotal Red 20 3 23 Orange 17 17 Dark Yellow 20 20 Yellow 19 19 Green 1 2021 Grand Total 20 20 20 20 20 80 % Exact Match 100.0% 85.0% 100.0% 95.0%100.0% — Exact Agreement: 95%

Those skilled in the art will appreciate that numerous changes andmodifications can be made to the preferred embodiments of the inventionand that such changes and modifications can be made without departingfrom the spirit of the invention. It is, therefore, intended that theappended claims cover all such equivalent variations as fall within thetrue spirit and scope of the invention.

The disclosures of each patent, patent application, and publicationcited or described in this document are hereby incorporated herein byreference, in its entirety.

EMBODIMENTS

The following list of embodiments is intended to complement, rather thandisplace or supersede, the previous descriptions.

Embodiment 1

A color chart comprising:

a surface material having one or more color swatches, wherein the colorswatches comprise one or more layers of a dried water color pigmentsolution, wherein the water color pigment solution contains colorpigment molecules.

Embodiment 2

The color chart of embodiment 1, wherein a color swatch having multiplelayers of a dried water color pigment solution has a darker hue comparedto a color swatch having fewer layers of the dried water color pigmentsolution.

Embodiment 3

The color chart of embodiment 1 or 2, wherein the one or more colorswatches are arranged in one or more color sections.

Embodiment 4

The color chart of embodiment 3, wherein the one or more color sectionscomprise a red color section, an orange color section, a yellow colorsection, a green color section, or any combination thereof.

Embodiment 5

The color chart of embodiment 4, wherein the yellow color sectioncomprises a dark yellow color section, a light yellow color section, orboth a dark yellow color section and a light yellow color section.

Embodiment 6

The color chart of embodiment 4 or 5, wherein

-   -   a. the red color section comprises a hue from about 347.1 to        about 360.0 or from about 0.0 to about 20.0;    -   b. the orange color section comprises a hue from about 24.1 to        about 36.7;    -   c. the yellow color section comprises a hue from about 38.4 to        about 57.0;    -   d. the green color section comprises a hue from about 74.5 to        about 120.0; or    -   e. any combination of a-d.

Embodiment 7

The color chart of any one of the previous embodiments, wherein thecolor of the one or more color swatches correlates with a color of oneor more water color pigment solutions.

Embodiment 8

The color chart of any one of the previous embodiments, wherein thewater color pigment solution comprises a suspension of one or more watercolor pigments.

Embodiment 9

The color chart of embodiment 8, wherein the one or more water colorpigments comprise orange, brilliant red, medium yellow, cobalt blue, rawumber, sap green, or any combination thereof.

Embodiment 10

The color chart of embodiment 8 or 9, wherein the one or more watercolor pigments comprises a combination of:

-   -   a) brilliant red and cobalt blue;    -   b) brilliant red and orange;    -   c) orange and medium yellow;    -   d) medium yellow and sap green; or    -   e) sap green and cobalt blue.

Embodiment 11

A water color pigment solution comprising:

a suspension of one or more water color pigments; and

urine or a solution that mimics urine.

Embodiment 12

The water color pigment solution of embodiment 11, wherein the one ormore water color pigments comprise orange, brilliant red, medium yellow,cobalt blue, raw umber, sap green, or any combination thereof.

Embodiment 13

The water color pigment solution of embodiment 11 or 12, wherein the oneor more water color pigments comprise a combination of:

-   -   a) brilliant red and cobalt blue;    -   b) brilliant red and orange;    -   c) orange and medium yellow;    -   d) medium yellow and sap green; or    -   e) sap green and cobalt blue.

Embodiment 14

The water color pigment solution of any one of embodiments 11-13,further comprising a preservative.

Embodiment 15

The water color pigment solution of embodiment 14, wherein thepreservative is sodium azide.

Embodiment 16

A method of calibrating a reflectance-based diagnostic analyzercomprising:

-   -   inserting the color chart of any one of embodiments 1-10 or the        water color pigment solutions of any one of embodiments 11-15        into the reflectance-based diagnostic analyzer, wherein the        color chart or the water color pigment solutions have a known        color;    -   obtaining reflectance values for the color chart or the water        color pigment solutions; and    -   if the obtained reflectance values do not correspond to the        known color of the color chart or the water color pigment        solutions, calibrating the analyzer such that the reflectance        values correspond to the known color of the color chart or the        water color pigment solutions.

Embodiment 17

The method of embodiment 16, wherein the reflectance-based diagnosticanalyzer is a portable diagnostic analyzer.

Embodiment 18

A kit comprising the color chart of any one of embodiments 1-10 or thewater color pigment solutions of any one of embodiments 11-15 andinstructions for using the color charts or water color pigmentsolutions.

Embodiment 19

The kit of embodiment 18, wherein the instructions explain to a user ofthe kit how to calibrate a reflectance-based diagnostic analyzer.

1. A color chart comprising: a surface material having one or more colorswatches, wherein the color swatches comprise one or more layers of adried water color pigment solution, wherein the water color pigmentsolution contains color pigment molecules.
 2. The color chart of claim1, wherein a color swatch having multiple layers of a dried water colorpigment solution has a darker hue compared to a color swatch havingfewer layers of the dried water color pigment solution.
 3. The colorchart of claim 1, wherein the one or more color swatches are arranged inone or more color sections.
 4. The color chart of claim 3, wherein theone or more color sections comprise a red color section, an orange colorsection, a yellow color section, a green color section, or anycombination thereof.
 5. The color chart of claim 4, wherein the yellowcolor section comprises a dark yellow color section, a light yellowcolor section, or both a dark yellow color section and a light yellowcolor section.
 6. The color chart of claim 4, wherein a. the red colorsection comprises a hue from about 347.1 to about 360.0 or from about0.0 to about 20.0; b. the orange color section comprises a hue fromabout 24.1 to about 36.7; c. the yellow color section comprises a huefrom about 38.4 to about 57.0; d. the green color section comprises ahue from about 74.5 to about 120.0; or e. any combination of a-d.
 7. Thecolor chart of claim 1, wherein the color of the one or more colorswatches correlates with a color of one or more water color pigmentsolutions.
 8. The color chart of claim 1, wherein the water colorpigment solution comprises a suspension of one or more water colorpigments.
 9. The color chart of claim 8, wherein the one or more watercolor pigments comprise orange, brilliant red, medium yellow, cobaltblue, raw umber, sap green, or any combination thereof.
 10. The colorchart of claim 8, wherein the one or more water color pigments comprisesa combination of: a) brilliant red and cobalt blue; b) brilliant red andorange; c) orange and medium yellow; d) medium yellow and sap green; ore) sap green and cobalt blue.
 11. A water color pigment solutioncomprising: a suspension of one or more water color pigments; and urineor a solution that mimics urine.
 12. The water color pigment solution ofclaim 11, wherein the one or more water color pigments comprise orange,brilliant red, medium yellow, cobalt blue, raw umber, sap green, or anycombination thereof.
 13. The water color pigment solution of claim 11,wherein the one or more water color pigments comprise a combination of:a) brilliant red and cobalt blue; b) brilliant red and orange; c) orangeand medium yellow; d) medium yellow and sap green; or e) sap green andcobalt blue.
 14. The water color pigment solution of claim 11, furthercomprising a preservative.
 15. The water color pigment solution of claim14, wherein the preservative is sodium azide.
 16. A method ofcalibrating a reflectance-based diagnostic analyzer comprising:inserting the color chart of claim 1 into the reflectance-baseddiagnostic analyzer, wherein the color chart or the water color pigmentsolutions have a known color; obtaining reflectance values for the colorchart or the water color pigment solutions; and if the obtainedreflectance values do not correspond to the known color of the colorchart or the water color pigment solutions, calibrating the analyzersuch that the reflectance values correspond to the known color of thecolor chart or the water color pigment solutions.
 17. The method ofclaim 16, wherein the reflectance-based diagnostic analyzer is aportable diagnostic analyzer.
 18. A kit comprising the color chart ofclaim 1 and instructions for using the color charts or water colorpigment solutions.
 19. The kit of claim 18, wherein the instructionsexplain to a user of the kit how to calibrate a reflectance-baseddiagnostic analyzer.